Alternating-current telegraph system



May 27, 1930: A. 1.. MATTE 1,759,950

ALTERNATING CURRENT TELEGRAPH SYSTEM Fild Feb. 25. 1928 h A A M V v v vv Zine Fllter IN V EN TOR.

ZZ. Waite C mom f Vent the transmission to therectiiierofh frequency"Waves correspo riding, t9, the: break I frequency.carr1er-wave.k, 3

quency to perrnit the cle fment'sof both half cycles,fand means to'preif,

ing-lup operation in y the 'ebs'e'nc alternating current wavesofsubstantially uniform low frequen y, a receiving' 'arrangecarrier waye of a trainro f carrier wavescor- "respon'dingtoa codeelement, at arelatively high frequency rate to, enable-the rectifier to c rectifyelements corresponding to both positive and negativefhalfcycl'e 20carrier telegraph systenrfin whicheach code element is transmitted'zi s:alirnited number of v {alternating current Waves substantially i vuniform lowfrequency, .dvreceiying"arranger -ment comprising means torectify halttvaves ofonly one polarity, a'nd means to interrupt bothpositive and negative hal'fcycles of each A. 'a low frequencyalternating "current I of only onepolarity, means to' interrupti hoth.positive and negative hal fcyclesof each car Irieri'wayeoffs;ltrain-of:cir'rieriwayes corre-' r sponding to. a. code'ele rnentf'aberelatively y I 9 high frequency, rate r to enable the,rectifier'fto Y I rectify elements "corresfionding to both ip'osi-i tiveand negetive hatlfcyciegflendmeans to;

preyent theaction 'of saidinterrupting-means I from affectin 1152 1 lowfrequency-carrier wave.

'5. In a low frequencyf' alternatlng yrier current upon the circuit o'7. In a transmisslon system, atra'nsformer short circuiting connectionof the buzzer be-. I I i 1 ing established at such points in the circuitthat no change in potential will appear upon i the grid'circuit-o'fsaiddetector'in the; ab f:

lternating carg. v V

sence of the low frequency means toapply a code element comprising a;

plurality .of cycles of alternating current of substantially constantlow-frequency'to the primary of said transformer, and meansto' iperiodicallydischarge the field'of'said transe former: at asfrequencyirate Which'fis'high as V L -f compared with the' frequency ofsaid alter-j natingcurrent. f

8. In a transmissioncsystemya, transformer "l means .t'o ap ply. a codeelement comprising a, H v l rplurality ofcycles of alternatingcurrentfofY a c substantially constant 10W frequencyto'the p'rimaryof saidtransformer, and means to j periodically discharge the field of saidtrans formerat-afrequency ratewhichfis high as I or comparedwith thefrequency of said alternate 5 v 'ing currentjthereby producingapluralityof j: alternatiyeweveforms for each'halicycle of;'said'alternating current, anda rectifierasso-j Y Y ciated With.seidftransformer to rectifyssaid 1-1 waveformsp In testimony whereof,'I' have signed-my r v Lna'me toj this specification this 21st dayf'pfwFehruary 1928.

g'the rectifier in thie absenceof a??? y I I "current v carrier.tele'graph sy'stemkin 'Which'each code element, istransmittedasa-1iinited number of v v c alternating'gfcurrentlwaves; o'fisuhstantially u i or w7f eqi e i y,ge ec iv ngs i 'c o p elfi t i fleces a "tm 7' l former 1n;.theLgr1d"circuitRot :sa 'd detector,

' c and la n .b'uzzerfconnected'"to "short jci rcuit' the: v

highfrequencyrategthereby fleguvey inter fprimary'of said.transformerfalt' drelati-velyf c p i ipd tive an etiv hl l sjor e chrrie ;cy le oft nefcarri 'w ves corresponding toacodeeleinenttogeneblegthef]; detector to rectify'componentscorresponding to both positive andfnegativeihelf'Tybls; 3 V j6;..In c'low'frequencyalt carrierltelegraph, systelni I 'e1eniei1tistrei'nsmittedasa niitedjnunihef of V chem-siting current wa es;

, iconiprising. a; rectifying detector, "at: trains; former inthe gridcircuit of said detiectofic- 1 I j i *buzzer connectedtoshorflcircuitthe primary L ofsaidtransfo'rmer at wrelatiyely high st-res, q encymthereby effectivelyinterrupting 1 both positive and negetiye'halyesofgach "caLr' i ib 1 0M tr i ofi r er; j escb e 1 'spondingto a;code' elen enttoenable the de V ctq c fy cqi pb i i fie r pefid i b bothpositiye and 'iiegat' u tan ial y uniform; low frequency, c a receivingcircuit

